1. Field of the Invention
The present invention relates to an improvement in an on-vehicle apparatus for use in a dedicated short-range communication system to be mounted on an automobile. More specifically, the invention relates to an on-vehicle apparatus provided with means for making use of one switch in a multifunctional way.
2. Description of the Related Art
In an automobile traveling on open roads, a Dedicated Short-Range Communication (hereinafter abbreviated as “DSRC”) system of Intelligent Transport Systems (hereinafter abbreviated as “ITS”) is getting popular. In the DSRC, the so-called on-vehicle apparatus provided with a radio communication section that performs communication with roadside radio equipment is used.
With this on-vehicle apparatus, a user (driver) can pay a turnpike toll, or can receive information regarding traffic jam situation of roads. Further, it is necessary for the on-vehicle apparatus to be mounted within easy reach of a driver so that the driver can operate it himself. Since the DSRC is a system that has recently started to be common, it is often attached to a vehicle afterward (i.e., the DSRC is attached after a vehicle has been manufactured and started in use). There are many cases where the DSRC is mounted on a dashboard onto which the DSRC is easily mounted. However, on the supposition that this apparatus may hinder vision, safety will be impaired, and therefore the on-vehicle apparatus is required to be as downsized as possible.
In order to meet such a request for downsizing, for example, an appearance of an on-vehicle apparatus is shown in FIG. 1 of the Japanese Patent Publication (unexamined) No. 150335/2000. On a front face of the on-vehicle apparatus of this drawing, there are provided two press button switches (external input sections 12, 13), a slot (5) into which a card such as cash card is inserted, and a display section (10). The two press buttons possess such single functions as are for sound volume setting or for history confirmation respectively. Further, in some apparatus, two switches have an UP/DOWN function by which a plurality of functions that are indicated on the display lined up vertically, are sequentially scrolled and selected.
In the initial stage when kind of services to be performed by a DSRC is only to pay the toll of a turnpike road, two press button switches are sufficient. However, in view of the situation that kind of services capable of being provided by a DSRC system has been increasing recently, the need to increase the number of press button switches arises.
However, this increase in number of press button switches induces the increase in panel area on the front face, which fact goes counter to the aforementioned request of downsizing. Thus, the number of press button switches cannot be increased. Consequently, a problem exists in that kind of services capable of being provided by an on-vehicle apparatus have to be limited. Moreover, since the apparatus of the above-mentioned selective type should be operated basically while visually reading characters or instruction on the display panel, it cannot be used during driving a vehicle. Thus, a further problem exits in that the apparatus of selective type cannot be basically employed as an on-vehicle apparatus.
As a matter of course, the art in which one switch has plural functions by making use of the so-called function key is generally applied to an electronic calculator or a cellular phone. However, the method of utilizing such a function key is less likely to apply without the assumption that instructions indicated on a switch face can be exactly read. Accordingly, operating a function key is difficult in DSRC on-vehicle apparatus that is often used while driving a car.